Andrew pillatt



(No Model.)

' A. PILLATT.

FURNAGEFOR WATER TUBE BOILERS. No. 605,511. Patented June l l, 1898.

W dn gg lgtm HLQUN NlTED STATES PATENT Erica;

FURNACE FOR WATER-TUBE BOILERS.

SPECIFICATION forming part of Letters Patent No. 605,511, dated June 14, 1898.

Application filed June 23, 1896. ri l N 596,579 (N0 111051810 To all whom it may concern.-

Be it known that I, ANDREW PILLATT, a subject of the Queen of Great Britain and Ireland, residing at Nottingham, England, have invented new and useful Furnaces for Water- Tube Boilers, of which the followingis a specification.

My invention relates to improvements in the furnaces of steam-boilers in which the flame plays outside and around the watertubes; and the object is to so construct and arrange these furnaces as to insure perfect combustion of the fuel-gases and promote economy and efficiency in working.

My improvements are particularly applicable to water-tubeboilers of the Babcock & WVilcoX, Hornsby, and like types.

I11 carrying out my invention I employ the hollow fire-bars, preferably those described in the specification of my British Letters Patent No. 13,371 of 1895-that is to say, hollow fire-bars extending through and opening behind the fire-bridge and formed with series of air-inlets arranged in the web or rib thereof. In combination with these bars I arrange in the upper part of the furnace a perforated refractory arch or roof of fire-brick, ganister, or the like, through the perforations in which the fuel-gases are drawn by the draft of the chimney.

My invention will be readily understood by reference to the accompanying drawings, in which Figure 1 represents a boiler of the type m en tioned fitted with myimproved furnace. Fig. 2 is a plan, and Fig. 3 a transverse section, of the arch or roof, these figures being drawn to a larger scale than Fig. 1.

a is the refractory arch or roof, which may be formed in halves or sections, as indicated by the central division-line, Figs. 2 and 3, to facilitate fitting in the furnace, and is perforated with slots or openingsb of any convenient shape and arrangement, whose total area may advantageously be equal or approxi mately equal to the area for the passage of the furnace-gases between the water-tubes. The said arch orroof is arranged at. a short distance below the water-tubes and at an inclination parallel with the said tubes. It springs from the side walls 0 of the furnace, where its edges are fitted in recesses o, and extends from the-furnace-front to the rear wall cl, so completely closing the upper part of the furnace save for the perforations above mentioned.

e are the fire-bars, (with lateral openings 8 proximately in the direction indicated by thefeathered arrows, Fig. 1. The course of the heated air from the ash-pit through the hollow fire-bars to thespace behind the rear wall (1 is as indicated by the plain arrows.

The arch a, by becoming highly heated, pro- I claim, and desire to secure by Letters Patent, is-

In a furnace for a boiler having water-tubes motes the combustion of the fuel-gases as they at an inclination above the bridge-wall, a perdescend from the perforated arch, substantially as set forth.

In witness whereof I have hereunto signed my name in the presence of two subscribing witnesses.

I ANDREW PILLATT.

Witnesses:

ANDREW ERNEST PILLATT, O. D. HEARN, Jr. 

